Fluid pump



P. G. KEMP FLUID PUMP July 20, 1954 Original Filed Oct. 2, 1947 MUH[NI/EDITOR. 1 /01/4 6. AfM/ Patented July 20, 1954 UNITED STATES FAT ENTOFFICE Original application October 2, 1947, Serial No.

777,443, new Patent No. 2,649,706, dated August 25, 1953.

Divided and this application November 23, 1949, Serial No. 128,963

4 Claims. 1

This invention relates to a pump for liquids of'the type having a rotaryimpeller and a plurality of vanes on the impeller for moving liquidthrough the pump.

t is an object of this invention to provide a rotary pump which isrelatively'small in size'but which is capable of delivering 'a largevolume of liquid at a relatively high pressure.

The pump of this invention is particularly adapted for-use on a washingmachineof the type wherein the washing action is obtained by directingstreams of water at the clothes at a relatively high velocity and fromdifferent angles. A washing machine of this type is disclosed in myco-pending application, Serial No. 777,443, filed October 2, 1947, nowPatent No. 2,649,706 issued August 25, 1953, of which this applicationis a division. In the drawings;

Figure 1 is a vertical sectionthrough thepump.

Figure 2 is a horizontal section taken along lines 2-2 in Figure 1.

In a. washing machine of the type disclosed in the above-mentionedco-pending application, the water which is directed against the clothesas jets is continuously recirculated and the pump of this invention isparticularly adapted for this purpose since the pump is small in sizeand capable of delivering a large volume of water at a relatively highpressure. It will be understood, however, that the use of my pump is notrestricted to washing machines and that the pump is adaptable for use ina large variety of different applications where it is desired to pumpliquids in large quantities and under relatively high pressure.

Since-the pump is admirably 'suitedfor the operation of a washingmachine of the above type, its construction and operation will bedescribed, for the purposes of illustration, in conjunction with awashing machine. Such a Washer is usually provided with an inlet inwhich leads to the water nozzles (not shown) and a drain pipe 12 whichconnects with the bottom of the washer tub (not shown). The pumpincludes a housing 14 having side walls It and it and a circumferentialwall 26. Wall i6 is formed with an inlet opening 22 at the centerthereof which extends axially into housing. M. At one side of the pump,the peripheral wall is intersected by :an outlet passage 2t. Outlet 24is arranged to be connected to the inlet it of the washer by a clamp 28.Inlet 22 is connected to the outlet l2 of the washer by a clampingmember 28.

Within housing It, there is arranged a rotor which comprises a pair ofspaced discs 32 and 34 which fit nicely within the peripheral wall'128of a housing. Rotor 38 issuppo'rted'by a screw 35 which threads into theendof a driving shaft 38 driven by :a motor 49. Shaft 38 is journalledin a water tight packing gland 32 in the side wall 18 of the housing.

At a point just beyond outlet 24 (assuming clockwise rotation ofrotortfi'), there is attached to the circumferential wall '26, a taperedstep member M which fits between discs 32 and Stand whichgradually'increases in height in a counterclockwise direction as viewedin Figure 1. The high end of step Mi terminates abruptly as at E6 sothat the step provides a cam which drops on abruptly at its tail end.

The fluid is moved through the pump from the inlet 22 to the outlet 24-by a plurality of flexible vanes 48 which are pivotally supportedbetween discs 32 and 3'4,as by pins 59. Inlet 22 has an extension 52which projects axially into housing It and terminates at a'point spacedonly slightly from disc 31% of rotor 30. Each vane 18 is backed by apine-which'limits the pivotal movement of 'thevane and causes the vaneto assume the flexed position, shown in Figure l, with the pivoted end5% of the vane engaging the outer surface of extension .22 and with thefree end 53 of the vane wiping against the circumferential wall 2 8 ofhousing M. Varies 48, it will be noted, divide :the interior of housingM into a plurality of generally radially extending rotating chambers Forthe best efficiency of the pump, vanes 48 must be flexible enough toride up cam 44 without consuming too "much power and must be'highlyresilientsio as toiinstantaneously spring ibacl; to their normal'flexedcontour at the mo- :ment they trip over thelhigh end 46 of stepM. I have found that vanes formed of treated rubber are ideal forthistpurpose'.

Liquid is admitted into the pump, that is, into chamberstil, throughinlet ZZ-by means of a restricted opening 62 which is formedon the sideoflextension 52 opposite outlet 2 5. Opening 82 is arranged such thatwater is admitted to the chambers formed byvanes 48 just after the vaneshavedischarged the water through outlet 24 and at'the moment they "tripover the high end bit of step M. Opening 62 preferably extends axiallyacross the full width of vanes ii) and extends circumferentially ofextension 52 for a range of about to 150. I have found that with anopening of approximately the pump attains its maximum efiiciency.Openings considerably less than 126 provide too short a period for theentrance of water into chambers 60 and openings in excess of 150 admitwater over too wide a range and the water voided at outlet 24 wouldtherefore not be subjected to the desirable effect of the centrifugalforce produced by rotor 30. Theoretically the water from inlet 22 shouldbe available to the rotor vanes at the exact moment they trip over thehigh end of cam 44. In practice I have found that a lag occurs in theaction of vanes 48 and that the best performance of the pump is obtainedif the restricted opening in inlet extension 52 is advanced slightly inthe cycle so that water is actually admitted to a particular chamberjust before the free end of the forward vane of each chamber trips overthe high end of cam 44.

Assuming that motor 40 drives rotor 30 in a clockwise direction asviewed in Figure 1, each vane 48, after passing outlet 24, rides up thetapered step 44 and then suddenly drops oil? the high end of the step.As vanes 48 flex in traveling up the cam surface of step 44, thechambers between the vanes engaging step 44 are gradually reduced involume until the forward vane of the chamber reaches the end 46 of step44. As the vane trips over this end of the step it springs back to itsoriginal contour and in so doing produces a sudden enlargement of thechamber and creates a partial vacuum in the chamber behind it. Thissudden enlargement of the chamber causes a surge of water to flowthrough the restricted opening 02. The water flows into each chamber notbecause of gravity but because a partial vacuum is suddenly created inthe chamher just as the mouth of the chamber coincides with opening 52.The water thus admitted to the chamber is rotated by the vanes at a highvelocity and is discharged through outlet 24 at a relatively highpressure.

It will thus be seen that I have provided a pump for moving liquids,which is very efficient in proportion to its size. I have found thatwhen used on a washing machine of the type disclosed in my saidco-pending application, the pump can be driven by a small horse powermotor connected to the ordinary household electrical outlet. It is myopinion that the improved performance of my pump can be attributed tothe fact that the water is sucked into the pump not only through theaction of the rotating rotor but also because a partial vacuum iscreated in eachchamber at the moment the mouth of the chamber registerswith the restricted inlet opening 62.

What I claim is:

1. In a rotary fluid pump of the type having a generally circularhousing and a rotary impellor within said housing, a plurality offlexible and resilient vanes on said impellor arranged to wipe againstthe inner peripheral surface of said housing and dividing the housinginto a plurality of radial chambers, each of said vanes forming theforward wall of one chamber and the rearward wall of the next adjacentchamber, step means extending around a portion of the inner peripheralsurface of said housing, said step means tapering in thickness from oneend thereof to the other end thereof so that said step means increasesin height in the direction of rotation of said impellor, said step meansterminating abruptly at the high end thereof, inlet means projectingaxially into and through the central portion of said housing and havinga circumferential port at one side thereof, said port being arrange toadmit fluid in a radially outward direction into said chambers just aseach vane forming the forward wall of said chamber wipes over the highend of said step means, and an outlet on the periphery of said housingspaced circumferentially from said port and adjacent to but in advanceof the low end of said step means.

2. The combination as set forth in claim 1 wherein said port extendscircumferentially of said inlet means in the range of -150.

3. A rotary fluid pump comprising a housing of generally cylindricalshape, a cylindrical conduit projecting into said housing and extendingalong the axis thereof, a rotary impellor mounted within said housin onan axis concentric with the axis of the housing, a plurality of radiallyextending vanes supported at their inner ends on said impellor, saidvanes being formed of a resilient material and being mounted on saidimpellor with their outer ends wiping over the inner peripheral surfaceof said housing and with their supported ends wiping over the outerperipheral surface of said inlet conduit, means forming a step on aportion of the inner peripheral surface of said housing, said steptapering in thickness from one end thereof to the other end thereof sothat the step increases in height in the direction of rotation of saidimpellor, said step terminating abruptly at the high end thereof suchthat as the vanes wipe up said step the size of the adjacent chambers isprogressively decreased and as the vanes wipe past the high end of saidstep the size of said adjacent chambers is suddenly increased and asudden partial vacuum is produced therein, said inlet conduit having acircumferential opening therein arranged to communicate with eachchamber between the inner supported ends of said vanes substantially atthe moment said partial vacuum is produced in said chamber, and outletmeans on the periphery of said housing adjacent and in advance of thelow end of said step means, said vanes being of sufficient length towipe against the inner peripheral surface of said housing except at saidoutlet means.

4. The combination set forth in claim 3 wherein said vanes are pivotedat their inner ends on said impellor, the length of said vanes beingsubstantially greater than the radial distance between the innerperipheral surface of said housing and the outer peripheral surface ofsaid inlet conduit, and means for limiting the pivotal movement of saidvanes on said impellor such that they normally assume a flexed position.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date None Peters et al Oct. 31, 1835 2,189,356 Briggs Feb. 6, 194.02,332,411 Swanson et a1 Oct. 19, 1943 2,460,421 Kinconnon Feb. 1, 19492,466,440 Kiekhaefer Apr. 5, 1949 2,599,600 Arnold June 10, 1952 FOREIGNPATENTS Number Country Date 2,024 reat Britain of 1893 47,930 Norway May19, 1930 456,679 Great Britain Nov. 13, 1936

